org.xtce.toolkit

Class XTCECcsdsCucTimeHandler

java.lang.Object

org.xtce.toolkit.XTCECcsdsCucTimeHandler

All Implemented Interfaces:

XTCEAbsoluteTimeType

public class XTCECcsdsCucTimeHandler
extends Object
implements XTCEAbsoluteTimeType

This class implements CCSDS CUC time to support AbsoluteTimeDataType elements in an XTCE document.

CCSDS CUC time format is composed of three identification fields. These are the P-FIELD, the T-FIELD, and an optional second P-FIELD providing additional information to the first. This implementation supports the capability of the first P-FIELD and the T-FIELD only. The default number of octets is 7 where 4 octets are used for the seconds and 3 octets are used for the seconds fraction. This corresponds to bits 4,5,6,7 of the P-FIELD definition. The default epoch is TAI, although any epoch can be specified.

This class is applicable to AbsoluteTimeType XTCE specifications when three conditions are met by the XML document:

• Encoding size in bits of the type element is equal to the sum of the octet sizes for the seconds and fraction seconds (default 56=7).
• Encoding is Unsigned Integer
• Epoch of the type element is equal to "TAI", "1958-01-01", or the custom epoch specified. All midnight GMT assumed.

Although the CCSDS specification carries as low as 2^-24 second counts, the basic demo Java implementation here uses the basic libraries and will only act as far as the milliseconds. A production grade version of this would need a better underlying time library.

Author:

dovereem

Constructor Summary

Constructors

Constructor and Description
XTCECcsdsCucTimeHandler() Default constructor to initialize a handler with the default time format and time zone.
XTCECcsdsCucTimeHandler(String timeFormat, String timeZone, String epoch, int numSecBytes, int numFracBytes) Constructor that permits changing the default time format and the time zone information.

Method Summary

Modifier and Type	Method and Description
String	getCalibratedFromUncalibrated(String uncalValue) Retrieve the EU calibrated value of this time item, which can be a Parameter or Argument, when given the uncalibrated value.
BitSet	getRawFromUncalibrated(String uncalValue) Retrieve the raw binary bits for encoding of this time item, which can be a Parameter or Argument, when given the uncalibrated value.
String	getUncalibratedFromCalibrated(String euValue) Retrieve the uncalibrated value for this time item, which can be a Parameter or Argument, when given the EU calibrated value.
String	getUncalibratedFromRaw(BitSet rawValue) Retrieve the uncalibrated value of this time item, which can be a Parameter or Argument, when given the raw binary value.
boolean	isApplicable(org.omg.space.xtce.AbsoluteTimeDataType instance) Method to determine if an XTCE AbsoluteTimeType, either Parameter or Argument, is handled by this implementation of the interface.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

XTCECcsdsCucTimeHandler

public XTCECcsdsCucTimeHandler()

Default constructor to initialize a handler with the default time format and time zone.

The default time output format is UTC ISO8601 text. This is in the form of YYYY-MM-dd HH:MM:ss.SSS

XTCECcsdsCucTimeHandler

public XTCECcsdsCucTimeHandler(String timeFormat,
                               String timeZone,
                               String epoch,
                               int numSecBytes,
                               int numFracBytes)

Constructor that permits changing the default time format and the time zone information.

Parameters:

timeFormat - String containing the time format string suitable for the Java SimpleDateFormat formatter.

timeZone - String containing the time zone identifier string, suitable for the TimeZone.getTimeZone method in Java.

epoch - String containing the epoch date in the form "yyyy-MM-dd" or the string "TAI".

numSecBytes - integer containing the number of bytes to use for the seconds field in the CCSDS CUC T-FIELD high bytes.

numFracBytes - integer containing the number of bytes to use for the fractional seconds field in the CCSDS CUC T-FIELD low bytes.

Method Detail

isApplicable

public boolean isApplicable(org.omg.space.xtce.AbsoluteTimeDataType instance)

Method to determine if an XTCE AbsoluteTimeType, either Parameter or Argument, is handled by this implementation of the interface.

This method returns true when three conditions are met by the XML that is represented by the JAXB AbsoluteTimeDataType object instance passed by the caller:

• Encoding size in bits of the type element is equal to the sum of the octet sizes for the seconds and fraction seconds (default 56=7).
• Encoding is Unsigned Integer
• Epoch of the type element is equal to "TAI", "1958-01-01", or the custom epoch specified. All midnight GMT assumed.

Specified by:

isApplicable in interface XTCEAbsoluteTimeType

Parameters:

instance - AbsoluteTimeDataType object from the JAXB representation of the XTCE XML document.

Returns:

boolean indicating if this handler supports/implements handling for the user provided Absolute Time Type, as specified in the XML.

getUncalibratedFromRaw

public String getUncalibratedFromRaw(BitSet rawValue)

Retrieve the uncalibrated value of this time item, which can be a Parameter or Argument, when given the raw binary value.

This conversion uses only system time capabilities, and as a result is not leap second corrected.

Specified by:

getUncalibratedFromRaw in interface XTCEAbsoluteTimeType

Parameters:

rawValue - BitSet containing the raw binary value that would be encoded on the wire or bitfield. The raw binary is always expected to be in the order read from the stream.

Returns:

String containing the integral microseconds since epoch.

getCalibratedFromUncalibrated

public String getCalibratedFromUncalibrated(String uncalValue)

Retrieve the EU calibrated value of this time item, which can be a Parameter or Argument, when given the uncalibrated value.

The uncalibrated input string contains an integral number of microseconds since the UNIX epoch. The output string is the UTC string in the form of ISO8601 (YYYY-MM-DD HH:MM:SS.sssss). The timezone is always UTC/GMT.

Specified by:

getCalibratedFromUncalibrated in interface XTCEAbsoluteTimeType

Parameters:

uncalValue - String containing the uncalibrated value that is derived from the encoded value on the wire or bitfield.

Returns:

String containing the proper EU calibrated representation of the uncalibrated value provided by the caller.

Throws:

NumberFormatException - in the event that the uncalibrated value cannot be converted to an integral number.

getRawFromUncalibrated

public BitSet getRawFromUncalibrated(String uncalValue)

Retrieve the raw binary bits for encoding of this time item, which can be a Parameter or Argument, when given the uncalibrated value.

This conversion uses only system time capabilities, and as a result is not leap second corrected.

Specified by:

getRawFromUncalibrated in interface XTCEAbsoluteTimeType

Parameters:

uncalValue - String containing the uncalibrated representation of the value.

Returns:

BitSet containing the raw bits.

Throws:

NumberFormatException - in the event that the uncalibrated value cannot be converted to an integral number.

getUncalibratedFromCalibrated

public String getUncalibratedFromCalibrated(String euValue)

Retrieve the uncalibrated value for this time item, which can be a Parameter or Argument, when given the EU calibrated value.

The uncalibrated output string contains an integral number of microseconds since the UNIX epoch. The input string is the UTC string in the form of ISO8601 (YYYY-MM-DD HH:MM:SS.sssss).

Specified by:

getUncalibratedFromCalibrated in interface XTCEAbsoluteTimeType

Parameters:

euValue - String containing a value of this item represented in EU/calibrated form.

Returns:

String containing the uncalibrated value.

Throws:

RuntimeException - in the event that a checked exception is caught by this function, with the parsing error text copied.